Aims: Catheter ablation for atrial fibrilation (AF) treatment provides effective and durable pulmonary vein isolation associated with encouraging clinical outcome data. The novel QDot ablation catheter provides very high-power short duration (radiofrequency (RF) energy: 90W/4 seconds) by the temperature controlled Qmode plus ablation modus to possibly improve safety and decrease ablation procedure time. Here we present the first experience utilizing this novel technology.

Methods: Twenty consecutive patients with paroxysmal or persistent AF were prospectively enrolled, and underwent Qmode plus based PVI. Three-dimensional electroanatomic LA reconstruction (CARTO 3, V7, Biosense Webster) was performed via a multielectrode spiral mapping catheter based fast anatomical mapping. Selective angiography of each pulmonary vein (PV) was then performed and the ipsilateral PVs were tagged. During PVI a multielectrode spiral mapping catheter was positioned inside the ipsilateral PVs. For PVI only the Qmode plus (90W/4 seconds) have been used. For anterior lesions an interlesion distance of 3-4 mm was used while for posterior lesions an interlesion distance of 5-6mm was used. An esophageal temperature probe was utilized in all cases to assess esophageal temperature (Teso).

Results: All PVs were successfully isolated utilizing the Qmode plus. First pass isolation was observed in 30/40 ipsilateral PVs (75%). Additional CTI block was performed in 4/20 cases, furthermore a roof line was performed in 2/20 and an anteriore line was performed in 1/20 caseses. The total median RF ablation time was 362 (322, 428) seconds, the median procedure time was 60 (range 56-74) minutes and the median fluoroscopy time was 7 (range 3-13) minutes The maximum Teso was measured 44,4°C. No periprocedural complications occurred during the procedures.